Knead butter, 100 g sugar, salt, vanillin sugar, spelt flour and grist into crumbles. Wash apples, grate dry. Cut out the core. Drizzle apples with lemon juice. Grease casserole dish.
Put in the apples. Spread crumbles on top. Bake in the preheated oven (electric cooker: 175 °C/ convection oven: 150 °C/ gas: level 2) for 25-30 minutes. Sprinkle almonds over the dough 10 minutes before the end of the baking time.
In the meantime, stir the sauce powder, 3 tablespoons of sugar and 6 tablespoons of milk until smooth. Boil up the rest of the milk. Stir in the sauce powder, boil again for about 1 minute and let it cool down a bit. Remove the baked apple crumble from the oven and dust with icing sugar.
Serve with the vanilla sauce.